The renal arteries normally arise off the abdominal aorta and supply the kidneys with blood. The arterial supply of the kidneys is variable and there may be one or more renal arteries supplying each kidney. Due to the position of the aorta, the inferior vena cava and the kidneys in the body, the right renal artery is normally longer than the left renal artery. The right renal artery normally crosses posterior to the inferior vena cava.

The renal arteries carry a large portion of total blood flow to the kidneys. Up to a third of total cardiac output can pass through the renal arteries to be filtered by the kidneys.

Diseases of the renal arteries

Renal artery stenosis, or narrowing of one or both renal arteries will lead to hypertension as the affected kidneys release renin to increase blood pressure to preserve perfusion to the kidneys.

Atherosclerosis can also affect the renal arteries and can lead to poor perfusion of the kidneys leading to reduced kidney function and, possibly, renal failure.